1. Field of the Invention
The present invention relates to an IC card connector which is mounted to an apparatus used by inserting an IC card into it and, in particular, to an improvement of an eject mechanism for separating an IC card inserted in the connector from pin contacts.
2. Description of the Related Art
An IC card connector is usually substantially equipped with a pin header portion in which a large number of pin contacts for connection to socket contacts in the IC card are arranged in a pin housing, a frame for guiding the IC card when it is inserted or extracted, an eject mechanism portion for separating the IC card in the inserted state from the pin contacts, etc. The above-mentioned eject mechanism portion comprises a push rod that is depressed when extracting the IC card, a lever member rotatably supported by the pin housing, etc. When the push rod is depressed with the IC card inserted in the connector, the lever member, which is adapted to rotate upon the depressing of the push rod, pushes out the IC card to a discharge position.
A conventional example of such an IC card connector as disclosed in Japanese Patent Laid-Open No. 9-82409 will be described. FIG. 7 is a bottom view of the conventional IC card connector with an IC card inserted therein, and FIG. 8 is a bottom view of the IC card connector in the eject state.
The IC card connector shown in these drawings mainly comprises a pin header (not shown) formed by forcing in and fastening in a predetermined arrangement a large number of pin contacts for connection to socket contacts in the IC card 1, a frame 2 which has a pair of grooves 2a for guiding the IC card 1 widthwise on either side when the card is inserted or extracted and which has a substantially U-shaped configuration in plan view, an eject lever 3 mounted to this frame 2, a driver lever 4, a push rod 5, etc. A bridge portion 2b of the frame 2 is opposed to the upper surface of the pin housing of the above-mentioned pin header. The eject lever 3 and the drive lever 4 are respectively rotatably supported by a first support shaft 6 and a second support shaft 7 mounted to the bridge portion 2b of the frame 2. The push rod 5, which is depressed when extracting the IC card 1, is held so as to be capable of reciprocating in the IC card inserting/extracting directions (the directions indicated by arrows A of FIG. 7) by support frames 2c protruding from two positions on a side surface of the frame 2. An eject mechanism portion is formed by the eject lever 3, the drive lever 4 and the push rod 5.
The eject lever 3 has in its one end portion a claw portion 3a for pushing out the IC card 1. The other end portion thereof is engaged with the rear end portion of the push rod 5. Somewhere between the two end portions, there is formed a recessed engagement step portion 3b. The drive lever 4 has in its end portion which is nearer to the push rod 5 a claw portion 4a for pushing out the IC card 1; in the other end portion thereof, there is formed a protruding engagement step portion 4b. The eject lever 3 and the drive lever 4 are joined together by slidably fitting together the engagement step portions 3b and 4b; upon the rotation of the eject lever 3, the drive lever 4 rotates in the reverse direction.
In this IC card connector, constructed as described above, as the IC card 1 is inserted from the card inserting portion of the frame 2, the IC card 1, which moves toward the above-mentioned pin header while being guided by the pair of grooves 2a, forces the pin contacts of the pin header into its socket contacts while pushing in the claw portion 3a of the eject lever 3 and the claw portion 4a of the drive lever 4, so that, by inserting the IC card 1 a predetermined distance, an insertion completed state is attained, in which, as shown in FIG. 7, the IC card 1 is reliably connected to each pin contact. At this time, being pushed in by the card inserting/extracting surface 1a of the IC card 1, the eject lever 3 and the rotation lever 4 are rotated around the first support shaft 6 and the second support shaft 7, respectively, in directions opposite to each other, and, with this rotation of the eject lever 3, the push rod 5 moves forward.
Further, when the push rod 5 is depressed with the IC card 1 inserted in the connector, the eject lever 3 is driven by this push rod 5 to rotate clockwise as seen in FIG. 7; since this torque is transmitted to the drive lever 4 through the engagement step portions 3b and 4b, the drive lever 4 rotates counterclockwise as seen in FIG. 7. As a result, the claw portions 3a and 4a of the eject lever 3 and the drive lever 4 push in the end portions of the card inserting/extracting surface 1a of the IC card 1, and, as shown in FIG. 8, the IC card 1 is separated from the pin contacts and pushed out to the discharge position, so that the card can be easily extracted by the fingers.
In the above-described conventional IC card connector, the eject lever 3, which rotates around the first support shaft 6, and the drive lever 4, which rotates around the second support shaft 7, are rotatably joined together by means of the engagement step portions 3b and 4b, so that the amount the drive lever 4 rotates with respect to the amount the push rod 5 is pushed in is determined by the distance between the second support shaft 7 and the engagement step portions 3b and 4b. Thus, when the distance between the second support shaft 7 and the engagement step portions 3b and 4b is set to be long, the moment of the drive lever 4 increases, so that the IC card 1 can be reliably separated from the pin contacts even if the push rod 5 is pushed in with a slight operating force. On the other hand, the rotation angle of the drive lever 4 decreases, so that the IC card 1 cannot be pushed out to a sufficient degree. In this way, a reduction in the operating force applied to the push rod 5 is not compatible with an increase in the amount the IC card is discharged. Under the circumstances, in setting the distance between the second support shaft 7 and the engagement step portions 3b and 4b, the amount the IC card is discharged takes priority over reduction in the operating force applied to the push rod 5, so that the amount the IC card is discharged cannot be increased with a slight operating force.